So I guess in the nearby 50 years Russia will keep pretending that we aren't interested in any EU or Eurozone participation
In these years Russia can dissolve again - just like in 1990 - oppressive dictatorships do not last forever - just like USSR, and now - Arab world.
Egyptian dictator Mubarak probably did not think in 2010, that in the next year he will be put to trial...

And after dissolution - parts of Russia's European half might join EU/Eurozone or even NATO - just like it happened with parts of former USSR - Baltics joined, and there are ongoing talks with Ukraine and Georgia.